Dehumidifier for a closed vehicle headlamp housing

ABSTRACT

A device for dehumidifying a closed vehicle headlamp housing includes a box with an opening connecting the inside of the box with the inside of the closed housing, and an opening connecting the inside of the box with the outside of the closed housing. The device further includes a shutter for alternatively opening the opening or sealingly closing it, an actuation module configured such that the shutter closes the opening when it is activated, and a heating element for emitting heat when the actuation module is activated.

TECHNICAL SCOPE

The present invention relates to the field of vehicle headlamps withclosed housing, and more particularly to a device suitable for beingused to dehumidify a closed vehicle headlamp housing.

STATE OF THE ART

Headlamps constitute an important element in the safety of vehicles, inparticular when the vehicle is driven at night or in atmosphericconditions requiring the use of lighting.

Generally, a vehicle headlamp comprises a housing closed by a glass andwherein is housed a light source. The housing not often being sealed,moisture can enter the housing and condense on the lens. Thiscondensation has an influence on the lighting efficiency of theheadlamp.

PRESENTATION OF THE INVENTION

The present invention relates to a device suitable for being used todehumidify or for preventing moisture from occurring in a closed vehicleheadlamp housing, thereby overcoming the abovementioned disadvantage.

For this purpose, the invention concerns a device suitable for beingused to dehumidify a closed vehicle headlamp housing or for preventingmoisture from occurring in said closed housing.

According to the invention, the device comprises:

-   -   a first box (2) defining a first chamber (5), the first box (2)        comprising at least two series of orifices (3, 4), each series        of orifices (3, 4) comprising at least one orifice, a first        series of orifices (3) being configured so that the first        chamber (5) communicates with the inside of the closed housing        (15) and a second series of orifices (4) being configured so        that the first chamber (5) communicates with the outside of the        closed housing (15),    -   at least a first shutter (7) configured to alternatively open        the orifice or the orifices of the first series of orifices (3)        or to close in a sealed manner the orifice or the orifices of        the first series of orifices (3),    -   an actuation module (8) configured so that the first shutter or        shutters (7) close the orifice or the orifices of the first        series of orifices (3) when the actuation module (8) is        activated,    -   a heating element (9) configured to emit heat when the actuation        module (8) is activated.

Thus, the device, which can be associated to a moisture absorber, allowsmoisture that risks condensing on the glass of the housing to beefficiently evacuated via the second orifice, thanks to the firstshutter that prevents moisture, that has entered the box, to exit.

Furthermore, the device comprises at least a second shutter configuredto, alternatively:

-   -   open the second series of orifices when the first shutter or        shutters close the first series of orifices, or    -   close the second series of orifices when the first shutter or        shutters open the first series of orifices.

Furthermore, the device comprises a second box defining a secondchamber, the second box being configured so that the second chambercommunicates with the first chamber via the second series of orifices,the second box comprising a third series of orifices configured so thatthe second chamber communicates with the outside of the closed housing.

According to a first example, the actuation module comprises:

-   -   a closing sub-module configured to close the first series of        orifices via the first shutter or shutters when said actuation        module is activated,    -   a return sub-module configured to bring the first shutter or        shutters to open the first series of orifices, when said        actuation module is inactivated.

Furthermore:

-   -   the closing sub-module is also configured to open the second        series of orifices via the second shutter or shutters when said        actuation module is activated,    -   the return sub-module is also configured to bring the second        shutter or shutters to close the second series of orifices when        said actuation module is inactivated.

According to a second example, the first shutter or shutters comprise afirst plate parallel to a plane containing the first series of orifices,the first plate comprising at least a first open part and at least afirst sealing part,

the actuation module being configured to move the first plate parallelto the plane containing the first series of orifices so that the firstplate occupies alternatively at least one or the other of the followingpositions:

-   -   a first position wherein the first open part or parts coincide        with the orifice or orifices of the first series of orifices to        open the orifices of the first series of orifices, or    -   a second position wherein the first sealing part or parts        coincide with the orifice or orifices of the first series of        orifices to close the orifices of the first series of orifices.

Furthermore, the second shutter or shutters comprise a second plateparallel to a plane containing the second series of orifices, the secondplate comprising at least a second open part and at least a secondsealing part,

the actuation module being also configured to move the second plateparallel to the plane containing the second series of orifices so thatthe second plate occupies alternatively at least one or the other of thefollowing positions:

-   -   a first position wherein the second open part or parts coincide        with the orifice or orifices of the second series of orifices to        open the orifices of the second series of orifices, when the        first plate is in its second position, or    -   a second position wherein the second sealing part or parts        coincide with the orifice or orifices of the second series of        orifices to close the orifices of the second series of orifices,        when the first plate is in the first position.

According to a third example, the first shutter or shutters comprise afirst sealing plate parallel to a plane containing the first series oforifices,

the actuation module being configured to move the first sealing plate toa normal of the plane containing the first series of orifices so thatthe first sealing plate occupies at least one or the other of thefollowing positions:

-   -   a first position wherein the first sealing plate is pressed        against the orifice or orifices of the first series of orifices        to close the orifices of the first series of orifices, or    -   a second position wherein the first sealing plate is distant        from the orifice or orifices of the first series of orifices to        open the orifices of the first series of orifices.

Furthermore, the second shutter or shutters comprise a second sealingplate parallel to a plane containing the second series of orifices,

the actuation module being also configured to move the second sealingplate according to a normal of the plane containing the second series oforifices so that the second sealing plate occupies at least one or theother of the following positions:

-   -   a first position wherein the second sealing plate is pressed        against the orifice or orifices of the second series of orifices        to close the orifices of the second series of orifices when the        first sealing plate is in its second position, or    -   a second position wherein the second sealing plate is moved away        against the orifice or orifices of the second series of orifices        to open the orifices of the second series of orifices when the        first sealing plate is in its first position.

According to another specificity, the heating element corresponds to acomponent of the actuation module suitable for heating when theactuation sub-module is activated.

For example, the heating element comprises a heat resistance.

Furthermore, the heat resistance is configured to operate in an opencircuit when it reaches a predetermined temperature.

According to another example, the heating element comprises anelectromagnetic element.

According to a first embodiment, the device comprises a membrane sealingthe orifice or orifices of the third series of orifices, the membranebeing configured to let the water vapour contained in the second chamberor the first chamber out of the box.

The invention also concerns a vehicle headlamp comprising a housingsealed by a glass and housing at least one light source.

According to the invention, the housing comprises a wall through whichis fixed a device suitable for being used to dehumidify said housing orto prevent moisture from occurring in said closed housing as describedabove, the inside of the housing communicating with the first chamber ofthe first box of said device through the first series of orifices, theoutside of the housing communicating with the first chamber through thesecond series of orifices.

BRIEF DESCRIPTION OF THE FIGURES

The invention, with its characteristics and advantages, will emerge moreclearly upon reading the following description made with reference tothe appended drawings, wherein:

FIG. 1 represents a perspective view of the device for dehumidifying andpreventing moisture from occurring on the side of the first series oforifices according to one embodiment,

FIG. 2 represents a perspective view of the device on the side of thesecond series of orifices according to the embodiment of FIG. 1,

FIG. 3 represents a perspective view of the device on the side of thefirst series of orifices with a first shutter opening the first seriesof orifices according to the embodiment of FIG. 1,

FIG. 4 represents a perspective view of the device on the side of thefirst series of orifices, wherein the actuation module is visibleaccording to the embodiment of FIG. 1,

FIG. 5 represents a perspective view of the device on the side of thefirst series of orifices, wherein the heating element is visibleaccording to the embodiment of FIG. 1,

FIG. 6 represents a schematic view of a vehicle headlamp comprising thedevice,

FIG. 7 represents a perspective view of the device on the side of thefirst series of orifices according to another embodiment,

FIG. 8 represents a profile view of the shutters and of the actuationmodule according to the embodiment of FIG. 7,

FIG. 9 represents a perspective view of the device on the side of thesecond series of orifices according to the embodiment of FIG. 7,

FIG. 10 represents an exploded view of the device according to theembodiment of FIG. 7,

FIG. 11 represents a perspective view of the device on the side of thefirst series of orifices according to another embodiment,

FIG. 12 represents an exploded view of the device according to theembodiment of FIG. 11,

FIG. 13 represents a profile view of a cross-section of the devicewherein the first shutter or shutters close the first series of orificesaccording to the device of FIG. 11,

FIG. 14 represents a profile view of a cross-section of the devicewherein the second shutter or shutters close the second series oforifices according to the device of FIG. 11.

DETAILED DESCRIPTION

The following description is provided with reference to theabovementioned figures.

The invention concerns an active device 1. Said device 1 is suitable forbeing used to dehumidify a closed housing 15, in particular a housing 15of a vehicle headlamp 16. Said device 1 is also suitable for preventingmoisture from occurring in the closed housing 15.

In the following description, “the device suitable for being used todehumidify a closed housing or for preventing moisture from occurring insaid closed housing” is called “device” (FIGS. 1 to 5).

The device 1 comprises a box 2 defining a chamber 5 inside the box 2.The box 2 is provided with at least two series of orifices 3 and 4. Eachseries of orifices 3 and 4 comprises at least one orifice. A series oforifices 3 is configured so that the chamber 5 of the box 2 communicateswith the inside of the closed housing 15. A series of orifices 4 isconfigured so that the chamber 5 of the box 2 communicates with theoutside of the closed housing 15 (FIG. 5).

An environment communicating with another environment means that therecan be an exchange of fluid, such as water vapour, between bothenvironments.

In one embodiment, the device 1 also comprises a moisture absorber 6arranged in the chamber 5 of the box 2. The moisture absorber 6 issuitable for absorbing the moisture present in the chamber 5 of the box2 (FIG. 5). For example, the moisture absorber 6 comprises silica gel.However, the moisture absorber can comprise any type of compound orsystem enabling the absorption of at least a part of the moisture thatcan be contained in the box 2.

The device 1 comprises an actuation module 8 and at least one shutter 7configured to, alternatively, open the orifice or orifices of the seriesof orifices 3 or close in a sealed manner the orifice or orifices of theseries of orifices 3. The actuation module 8 is configured to commandthe shutter or shutters 7, i.e. it commands the shutter or shutters 7 sothat they close the orifice or orifices of the series of orifices 3 whensaid actuation module 8 is activated (FIG. 4).

Furthermore, the device 1 comprises a heating element 9 configured toemit heat when the actuation module 8 is activated.

According to one embodiment (FIGS. 7 to 14), the device comprises atleast one second shutter 18 configured to, alternatively:

-   -   open the second series of orifices 4 when the first shutter or        shutters 7 close the first series of orifices 3 or,    -   close the second series of orifices 4 when the first shutter or        shutters 7 open the first series of orifices 3.

According to a preferred embodiment, the device 1 further comprises abox 19 defining a chamber 20. The box 19 is configured so that thechamber 20 communicates with the chamber 5 through the series oforifices 4. The box 19 comprises a series of orifices 21 configured sothat the chamber 19 communicates with the outside of the closed housing15.

According to a first example (FIGS. 1 to 5), the actuation module 8comprises:

-   -   a closing sub-module configured to close the series of orifices        3 via the shutter or shutters 7 when the actuation module 8 is        activated,    -   a return sub-module, such as a spring, configured to force the        shutter or shutters 7 to open the series of orifices 3 when said        actuation module 8 is inactivated.

In this first example, when the actuation module 8 is activated, theclosing sub-module exerts a force acting against the force exerted bythe return sub-module so that the shutter or shutters 7 close the seriesof orifices 3.

According to a variant of the first example, the closing sub-module ofthe actuation module 8 is also configured to open the series of orifices4 via the shutter or shutters 18 when said actuation module 8 isactivated. Furthermore, the return sub-module is also configured tobring the shutter or shutters 18 to close the second series of orifices4 when said actuation module 8 is inactivated.

According to a second example (FIGS. 7 to 10), the shutter or shutters 7comprise a plate 23 parallel to a plane containing the series oforifices 3. The plate 23 comprises at least an open part 24 and at leasta sealing part 25. For example, the plate 23 comprises a full platecomprising openings. The open part or parts 24 correspond to one orseveral openings. The sealing part or parts 25 correspond to the partsbetween the opening or openings.

In this second example, the actuation module 8 is configured to move theplate 23 parallel to the plane containing the series of orifices 3 sothat the plate 23 occupies alternatively at least one or the other ofthe following positions:

-   -   a first position wherein the open part or parts 24 coincide with        the orifice or orifices of the series of orifices 3 to open the        orifices of the series of orifices 3, or    -   a second position wherein the sealing part or parts 25 coincide        with the orifice or orifices of the series of orifices 3 to        close the orifices of the series of orifices 3.

In these two positions, the plate 23 remains pressed against the seriesof orifices 3.

According to a variant of this second example, the shutter or shutters18 comprise a plate 26 parallel to a plane containing the series oforifices 4. Similarly to the first plate 23, the plate 26 comprises atleast an open part 27 and at least a sealing part 28.

In this variant, the actuation module 8 being also configured to movethe plate 26 parallel to the plane containing the series of orifices 4so that the plate 26 occupies alternatively at least one or the other ofthe following positions:

-   -   a first position wherein the open part or parts 27 coincide with        the orifice or orifices of the series orifices 4 to open the        orifices of the series of orifices 4, when the plate 23 is in        its second position, or    -   a second position wherein the sealing part or parts 28 are in        alignment with the orifice or orifices of the series orifices 4        to close the orifices of the series of orifices 4, when the        plate 23 is in its first position.

In these two positions, the plate 26 remains pressed against the seriesof orifices 4.

As represented in FIGS. 7 to 10, the actuation module 8 can move theshutter or shutters 7 and/or the shutter or shutters 18 by rotation. Theactuation module 8 can therefore comprise a motor provided with a motorshaft A perpendicular to the shutter(s) 7 and 18 and suitable forrotationally driving the plate 23 and/or the plate 26 about the axis ofthe motor shaft A or of a motor shaft B parallel to the motor shaft A bymeans of a gearing. Preferably, the motor is a direct current motor.

According to a third example (FIGS. 11 to 14), the shutter or shutters 7comprise a sealing plate 29 parallel to a plane containing the series oforifices 3.

In this third example, the actuation means 8 is configured to move thesealing plate 29 in translation according to a normal of the planecontaining the series of orifices 3 so that the sealing plate 29occupies at least one or the other of the following positions:

-   -   a first position wherein the sealing plate 29 is pressed against        the orifice or orifices of the series of orifices 3 to close the        orifices of the series of orifices 3, or    -   a second position wherein the sealing plate 29 is moved away        from the orifice or orifices of the series of orifices 3 to open        the orifices of the series of orifices 3.

In the variant of the third example, the shutter or shutters 18 furthercomprise a sealing plate 30 parallel to a plane containing the series oforifices 4.

In this variant, the actuation means 8 is also configured to move theplate 30 in translation according to a normal of the plane containingthe series of orifices 4 so that the sealing plate 30 occupies one orthe other of the following positions:

-   -   a first position wherein the sealing plate 30 is pressed against        the orifice or orifices of the series of orifices 4 to close the        orifices of the series of orifices 4 when the sealing plate 29        is in its second position, or    -   a second position wherein the sealing plate 30 is moved away        against the orifice or orifices of the series of orifices 4 to        open the orifices of the series of orifices 4 when the sealing        plate 29 is in its first position.

As represented in FIGS. 11 to 14, in this third example, the shutter orshutters 7 and/or the shutter or shutters 18 can be drivensimultaneously in translation by the actuation module 8. The actuationmodule 8 can therefore comprise a motor provided with a motor shaft Aparallel to the sealing plates 29 and 30 and suitable for driving theplate 29 and/or the plate 30 in translation by means of a gearing P.Preferably, the motor is a direct current motor.

Thus, when the shutter or shutters 7 are open, the moisture 17 containedin the housing 15 of the headlamp 16 enters in the box 2 of the device1.

For example, the moisture can be absorbed by a moisture absorber 6.

For example, the heat emitted by the heating element 9 is suitable fortransforming the moisture absorbed by the moisture absorber 6 into watervapour. The water vapour 11 is then evacuated via the orifice 4 towardsthe outside of the box 2.

According to one embodiment, the heating element 9 corresponds to acomponent of the actuation module 8 suitable for heating when theactuation sub-module is activated.

The heating element 9 can comprise or correspond to a heat resistance.The heat resistance is configured to operate in an open circuit when itreaches a predetermined temperature.

According to another example, the heating element 9 comprises anelectromagnetic element. The electromagnetic element can be anelectromagnet enabling the actuation module 8 to close the shutter 7when said actuation module 8 is activated.

The moisture absorber 6 can correspond to a component suitable forabsorbing moisture, such as silica gel. Said component can coat theinner surface of the box 2, but it can also be contained in an internalhousing provided near the heating element 9. The silica can also becontained in or on an adhesive support suitable to adhere onto a surfacecontained in the chamber 5.

According to one embodiment (FIG. 2), the device 1 comprises a membrane10 sealing the series of orifices 21. The membrane 10 is configured tolet the water vapour 11 present in the box 2 out of the chamber 20. Thewater vapour contained in the box 2 and evacuated by the series oforifices 21 can correspond to the moisture previously absorbed by themoisture absorber 6, which has been transformed into water vapour by theheat transmitted by the heating element 9 or to moisture contained inthe chambers 5, 20 and that has not been absorbed by the moistureabsorber 6.

The invention also concerns a vehicle headlamp 16 comprising a housing15 closed by a glass 13 and housing at least one light source 14 (FIG.6).

The closed housing 15 comprises a wall 12 through which is fixed adevice 1 such as described above.

The inside of the housing 15 communicates with the chamber 5 of thefirst box 2 of said device 1 via a series of orifices 3 and the outsideof the housing 15 communicates with the chamber 5 of the first box 2 ofsaid device 1 via the second series of orifices 4.

The present description details various embodiments with reference tothe figures and/or the technical characteristics. The person skilled inthe art will understand that the various technical characteristics andembodiments can be combined to obtain other embodiments, unless it isexplicitly mentioned otherwise or unless these technical characteristicsare incompatible. Likewise, a technical characteristic of an embodimentcan be isolated from the other technical characteristics of the sameembodiment, unless mentioned otherwise. In the present description,numerous specific details are provided by way of example and are in noway limited thereto, so as to detail precisely the invention. The personskilled in the art will however understand that the invention can beachieved in the absence of one or several of these specific details orwith variants. In other occasions, some aspects are not detailed toavoid obscuring and weighing down the present description, and theperson skilled in the art will understand that diverse and varied meanscan be used and that the invention is not limited to the describedexamples.

It should be obvious to persons skilled in the art that the presentinvention enables embodiments in many other specific forms withoutdeparting from the scope of the invention as claimed. Consequently, thepresent embodiments must be considered as examples, but can be modifiedwithin the scope of the appended claims, and the invention cannot belimited to the details provided below.

1. A device for dehumidifying a closed housing of a vehicle headlamp toprevent moisture from occurring in said closed housing, the devicecomprising: a first box defining a first chamber, the first boxcomprising at least two series of orifices, each series of orificescomprising at least one orifice, one first series of orifices beingconfigured so that the first chamber communicates with the inside of theclosed housing and a second series of orifices being configured so thatthe first chamber communicates with the outside of the closed housing,at least a first shutter configured to alternatively open the orifice ororifices of the first series of orifices and close in a sealed mannerthe orifice or orifices of the first series of orifices, an actuationmodule configured so that the first shutter or shutters close theorifice or the orifices of the first series of orifices when theactuation module is activated, a heating element configured to emit heatwhen the actuation module is activated.
 2. The device according to claim1, further comprising at least a second shutter configured to,alternatively: open the second series of orifices when the first shutteror shutters close the first series of orifices, and close the secondseries of orifices when the first shutter or shutters open the firstseries of orifices.
 3. The device according to claim 1, furthercomprising a second box defining a second chamber, the second box beingconfigured so that the second chamber communicates with the firstchamber via the second series of orifices, the second box comprising athird series of orifices configured so that the second chambercommunicates with the outside of the closed housing.
 4. The deviceaccording to claim 1, wherein the actuation module comprises: a closingsub-module configured to close the first series of orifices via thefirst shutter or shutters when said actuation module is activated, and areturn sub-module configured to bring the first shutter or shutters toopen the first series of orifices when said actuation module isinactivated.
 5. The device according to claim 4, wherein: the closingsub-module is configured to open the second series of orifices via thesecond shutter or shutters when said actuation module is activated, andthe return sub-module is configured to bring the second shutter orshutters to close the second series of orifices when said actuationmodule is inactivated.
 6. The device according to claim 1, wherein thefirst shutter or shutters comprise a first plate parallel to a planecontaining the first series of orifices, the first plate comprising atleast a first open part and at least a first sealing part, the actuationmodule being configured to move the first plate parallel to the planecontaining the first series of orifices so that the first plate occupiesalternatively at least one or the other of the following positions: afirst position wherein the first open part or parts coincide with theorifice or orifices of the first series of orifices to open the orificesof the first series of orifices, and a second position wherein the firstsealing part or parts coincide with the orifice or orifices of the firstseries of orifices to close the orifices of the first series oforifices.
 7. The device according to claim 1, wherein the second shutteror shutters comprise a second plate parallel to a plane containing thesecond series of orifices, the second plate comprising at least a secondopen part and at least a second sealing part, the actuation module alsobeing configured to move the second plate parallel to the planecontaining the second series of orifices so that the second plateoccupies alternatively at least one or the other of the followingpositions: a first position wherein the second open part or partscoincide with the orifice or orifices of the second series of orificesto open the orifices of the second series of orifices, when the firstplate is in its second position, and a second position wherein thesecond sealing part or parts coincide with the orifice or orifices ofthe second series of orifices to close the orifices of the second seriesof orifices, when the first plate is in the first position.
 8. Thedevice according to claim 1, wherein the first shutter or shutterscomprise a first sealing plate parallel to a plane containing the firstseries of orifices, the actuation plate being configured to move thefirst sealing plate according to a normal of the plane containing thefirst series of orifices so that the first sealing plate occupies atleast one or the other of the following positions: a first positionwherein the first sealing plate is pressed against the orifice ororifices of the first series of orifices to close the orifices of thefirst series of orifices, and a second position wherein the firstsealing plate is moved away from the orifice or orifices of the firstseries of orifices to open the orifices of the first series of orifices.9. The device according to claim 1, wherein the second shutter orshutters comprise a second sealing plate parallel to a plane containingthe second series of orifices, the actuation module also beingconfigured to move the second sealing plate according to a normal of theplane containing the second series of orifices so that the secondsealing plate occupies at least one or the other of the followingpositions: a first position wherein the second sealing plate is pressedagainst the orifice or orifices of the second series of orifices toclose the orifices of the second series of orifices when the firstsealing plate is in its second position, and a second position whereinthe second sealing plate is moved away against the orifice or orificesof the second series of orifices to open the orifices of the secondseries of orifices when the first sealing plate is in its firstposition.
 10. The device according to claim 1, wherein the heatingelement corresponds to a component of the actuation module that isconfigured to emit heat when the actuation sub-module is activated. 11.The device according to claim 1, wherein the heating element comprises aheat resistance.
 12. The device according to claim 10, wherein the heatresistance is configured to operate in an open circuit when the heatingelement reaches a predetermined temperature.
 13. The device according toclaim 1, wherein the heating element comprises an electromagneticelement.
 14. The device according to claim 1, further comprises furthercomprising a membrane sealing the orifice or orifices of the thirdseries of orifices, the membrane being configured to let water vapourpresent in the second chamber or in the first chamber out of the box.15. A vehicle headlamp comprising a housing closed by a glass andhousing at least one light source, wherein the housing comprises a wallthrough which is attached a device configured to dehumidify said housingor to prevent moisture from occurring in said closed housing accordingto claim 1, the inside of the housing communicating with the firstchamber of the first box of said device via the first series oforifices, the outside of the housing communicating with the firstchamber via the second series of orifices.